The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent that it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Catalytic converters are commonly used with internal combustion engines to reduce emissions. The catalytic converters generally operate more efficiently at elevated temperatures. When the engine is started, the catalytic converter may not be immediately effective in removing emissions from the exhaust until the catalytic converter reaches an operating temperature (e.g., a “light-off temperature”). The light-off temperature is a point where the conversion of carbon monoxide (CO), unburned hydrocarbons (HC), and nitride oxides (NOx) has reached 50% efficiency.
Preheating the catalytic converter by an external heating element (e.g., electric resistance heaters) may provide extra heat to the exhaust gas and the catalytic converter to reduce the time required to reach the light-off temperature. 12-volt electrical systems on most vehicles, however, do not provide enough energy to quickly pre-heat the heating element. It may take several minutes for the heating element to heat the catalytic converter to reach the light-off temperature before the engine can be started.